Problem 658. Find the biggest empty box
You are given a matrix that contains only ones and zeros. Think of the ones as columns in an otherwise empty floor plan. You want to fit a big square into the empty space (denoted by zeros). What is the largest empty square sub-matrix you can find in the given matrix? You will return the row and column extent of the sub-matrix. The answer may not be unique. We will test that your sub-matrix is square, that it is empty, and that it contains the correct number of elements.
Example:
 Input a = [ 1 0 0 
             0 0 0 
             0 0 0 ]
 Output si = [ 2 3 2 3 ]
That is, the square indices are a(2:3,2:3). We verify that sum(sum(a(2:3,2:3))) is zero, and that it has four elements.
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		8 Comments
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		    5 older comments
		  
		  
		David Hruska
    	on 9 Jun 2012
	
	
  	There appears to be an error is Test Suite #3.
		Richard Zapor
    	on 10 Jun 2012
	
	
  	Agree, len for Test Suite 3 should be 4 not 3.
		Ned Gulley
    	on 10 Jun 2012
	
	
  	Yes. Fixed it.
		Jean-Marie Sainthillier
    	on 29 Nov 2012
	
	
  	Very exciting, as always with Ned
		Brian Hannan
    	on 16 Jan 2015
	
	
  	Good puzzle!
		Jerivington
    	on 10 Jun 2016
	
	
  	Challenging like all the other problems set in the ASEE Challenge
		jmac
    	on 23 May 2020
	
	
  	Nice!
		Dyuman Joshi
    	on 9 Jul 2022
	
	
  	Test suite has been updated with unsymmetrical matrices.
The original problem description/statement doesn't mention any restriction on the input matrix size.
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